Fuel flowing through a fuel injector typically exits at a nozzle end of the fuel injector. The nozzle end is believed to have a disk with at least one orifice to control, in part, the spray pattern and the direction of the fuel exiting the fuel injector.
The orifice used in fuel injectors is believed to be formed by drilling through a workpiece that can be of a suitable cross section. The work piece is believed to be further machined so that the work piece can be assembled with the nozzle end of a fuel injector.
At least two laser-machining techniques are believed to be used for machining orifices. One is percussion drilling, and the other is trepanning or helical drilling. Percussion drilling is believed to be less than desirable due to a variation in beam profile and targeting or the random nature of metal heating and expulsion that most likely result in a non-cylindrical or non-circular orifice. Trepanning, on the other hand, is believed to be more precise as a center hole is believed to be initially formed before the formation of the orifice and is believed to create less debris during machining. Helical drilling is similar to trepanning but without the initial formation of a center hole.
Regardless of the techniques, a single laser is typically used to machine a single work piece at a time in such laser system. In order to maximize the use of the laser system, it would be desirable to increase the ability to form more than one orifice at a time on a single work piece or to form orifices on more than one work piece at a time. It would also be desirable to increase the number of consistent quality orifices produced by a single laser machining system.